Mold supporting device



Sept 15, 1953 R. P. DAVIS MOLD SUPPORTING DEVICE Filed April 17, 1951INVENTOR. Rag 012 R Dal/w. W// l%f Patented Sept. 15, 1953 UNITED STATESPATENT OFFICE MOLD SUPPORTING DEVICE Ralph P. Davis, Squantum, Mass.,assignor to Walworth Company, Boston, Mass., at corporation ofMassachusetts Application April 17, 1951, Serial No. 221,423

Claims. 1

This invention relates to casting apparatus and more particularly tosupporting devices for shelltype molds.

Molds of the thin walled shell-type are comprised of a major portion ofan inorganic molding material, such as sand, and a minor portion of ancomponent serving to bind the inorganic material. The completed moldsare in two or more matching parts having the form of hard, thin, shellsof substantial strength. The inner faces of the matching parts aresmooth and finished whereas the outer surfaces are left in a rough andirregular condition. Consequently, during the casting operation usingsuch molds the common weighting methods for ordinary sand molds cannotbe used with any degree of success.

In casting operations using shell-type molds it has been customary toimbed the mold parts in a loose, relatively coarse, granular materialwith the intention of enabling the mold to withstand the static pressureof the molten metal. Refractory materials, such as steel shot, sand andgravel have been proposed as suitable bedding material to be containedin the pouring box. It is diflicult, however, to support the two halvesof the mold in proper position within the casting box while therefractory material is loaded therearound.

An object of this invention is to support shelltype molds during theloading operation so that the operator is free to conduct the loadingoperation.

Another object of the invention is to support the mold in castingposition in a manner which will not fracture or otherwise destroy themold being supported.

Another object of the invention is to permit removal of the supportingdevice from the casting box in an expeditious manner after the castingoperation.

Another object of the invention is to retain broken mold parts and otherdebris remaining from the casting operation within the supporting devicefor removal therewith from the casting box and thus avoid contaminationof the loading material.

The supporting device for accomplishing these and other objects andadvantages of the invention comprises a generally rectangular casinghaving opposite side walls defining an opening adapted to receive themold. Mold support means extend across the casing between the side wallsthereof and may be arranged for adjustment to two or more operativepositions. A plurality of pivotally mounted retaining members arepositioned in the casing and adapted for engagement with opposite sidesof the mold for holding the same in position on the support. Theretaining members are disposed in opposite pairs on either side of themold for independent movement. Yieldable means is operable between eachof the opposite pairs for rotating the free ends of the retainingmembers toward each other and relative to the mold positionedtherebetween for retaining the same in position on the support means.

The side walls of the supporting device are provided with hooked endswhich provide for demountable attachment from a casting box of suitabletype. Such a casting box is fully disclosed and claimed in my copendingapplication, Serial No. 183,363, filed September 6, 1950. A screen ispositioned in the bottom of the supporting device for retaining brokenmolds and other debris within the supporting device for removaltherewith from the casting box following the casting operation.

In the accompanying drawings:

Fig. 1 is a side elevation of the supporting device,

Fig. 2 is a cross-section taken on the line IIII of Fig. 1.

Referring more particularly to the drawing, a pair of oppositelydisposed side-wall members I 0, I2 are provided with hooked ends M fordemountable attachment to a casting box as shown in broken lines. Themedian portion of each of the side-wall members [0, 12 at one endthereof is slotted,,as at [6, to jointly receive the opposite ends ofthe shell-type mold. A plurality, in this instance four, connectingmembers in the form of tie rods [8. are positioned at the opposite endof the side-wall portions ill, 12 for securing the same in spacedrelation. The arrangement of the side-wall portions [0, l2 and tie rodsIt forms a generally rectangular casing having opposite side wallsdefining an opening and provided with the slotted portions [6 and thehooked ends I i. The casing so formed is of sufiicient size to receivethe shell-type mold and also fit loosely within the casting box whensupported therein by the hooked ends [4. It will be understood that themold is spaced from the opposite side-walls of the casting boxsufficiently to provide for loading the refractory material therearoundas previously explained. However, the mold having its ends positionedinthe slotted portions I6 is adapted to be supported at other pointsduring the loading operation.

To this end, support means 2| for the mold bottom take the form of apair of longitudinal bars 20, 22 secured together in spaced relation bymeans of a plurality of cross-bar portions 24 which are suitablynotched, as at 26, to provide guide means for the lower edges of themold halves. The support bars 20, 22 and cross-bars 24 extend betweenand are supported in the sidewalls [0, 12 by head portions 28 secured ateither end to the support bars 20, 22 and which are suitably notched forengagement with a pair of projecting studs 39 carried by each of theside walls 10, I2 respectively. In order to provide for adjustment ofthe support means 2| relative to the side walls l0, 12, an additionalpair of studs '32 project from each of the side-walls 19., I2respectively in spaced relation to the studs 30. It will be apparentthat more than these two positions may be provided, if desired, by theuse of additional studs appropriately located on the sidewalls IO, 12.

A plurality of pairs, in this instance four pairs, of retaining membersin the form of :rodimembers 34 are pivotally mounted at one end on twoopposite tie bolts 16 to extend perpendicularly thereof toward the openend of the casing with the free ends extending beyond the support means21. The rod members 34 are disposed in opposite pairs on each of the twotie bolts 18 for operative en agement on either side of the mold and forindependent movement. The free ends of each of the pairs of rod members34 are connected by a cross-bar 36 for unitary movement of each pair.

Yieldable means in the form of a pair of tension springs 38 is operablerespectively between the opposite pairs of rod members 3 1 for biasingthe cross-bars 35 on opposite sides of the mold toward each other. Eachspring 38 has its opposite ends engaged with a pair of spring retainerbars 48 each of which is secured at opposite ends to the pairs of rodmembers 34 but preferably at the pivoted end thereof opposite thecross-bar 38. The coil springs 38 are chosen to cause the cross-bars 36to exert sufficient pressure on the mold halves to retain the same inposition on the support means 2|, but insufficiently to crush the moldso supported.

Stop means are employed for limiting movement of the rod members 34against the bias of the springs 38 and take the form of a plurality ofangular shaped support rods 42, four in this instance, one of which ispositioned on either side respectively of the rod members 34 andextending around. each of the four tie bars 18. The support rods may besecured by welding or other suitable means to the two opposite tie rodsl8 not carryin the pivoted ends of the rod members 34. A pair of tensionbars 44 are employed for connecting the opposite ends of each pair ofsupport rods 42 respectively and extend substantially parallel with thesprings 38 on either side thereof. Secured to each support bar 42 is apair of stop plates 45 which project transversely therefrom adjacenteach of the rod members '34 to limit movement thereof under bias of thesprings 38. Thus, the free ends of the rod members 34 carrying thecross-bars 3B are maintained in spaced relation for ready separation toinsert the mold. The support bars 42 provide convenient support for ascreen 48 for retaining broken molds and other debris from entering thecasting box to which the supporting device is applied.

The operation of the device will be apparent from the foregoingdescription. The device is applied to a suitable casting :box by thehooked ends 14. The cross-bars 36 at the free ends of the rod members 34may readily be separated from each other as described to insert a moldwith its opposite edges within the slotted portions i6 of the side-wallsl0, [2. The mold rests on the support means 2| which, as stated, issuitably notched at 26 for its reception. The cross-bars 36 androdmembers 34 are then released to engage the mold and retain it inposition during the shot loading operation.

After the casting operation, the mold is usually disintegrated and thepieces will fall on the screen i 48 without entering the casting box.The support of this invention may be removed at any time from thecasting box and emptied of debris as will be apparent. Many changes maybe made in the details of construction and arrangement of parts withinthe scope of the appended claims.

I claim:

1. A supporting device for a shell-type mold, comprising a pair of,oppositely disposed side-wall members, a plurality of connecting membersextending between said side-wan members and being connected thereto forretaining the same in spaced relation, support means carried by saidside-wall members, said support means extending between said side wallmembers and being adapted to engage the lower edge of a mold to supportthe same, and means for preventing lateral displacement of a mold onsaid support means including at least two oppositely disposed memberspivotally mounted on said connecting members, yieldable means forbiasing said pivoted members to' -ard each other for engagement with themold on support means-and stop means for limiting said pivotal movementunder said bias to maintain a spaced relation between said pivotedmembers in the biased position thereof.

A mold supportingdevice as claimed in claim 1 wherein said yieldablemeans comprises a spring acting between said pivoted members to bias thesame toward said stop means.

3. ,A mold supporting device as claimed in claim- 1 wherein said sidewall members are slotted at the median portion thereof to receive theends of the mold and prevent lateral displacement thereof.

A mold supporting device asclaimed in claim 3 wherein said support meansinclude a bar having guide means extending longitudinally be tween saidslotted portions and supported by said side wall members.

5. A mold supporting device as claimed in claim 3 wherein said side wallmembers are provided with hooked ends adapted for demountableattachment, on a casting box, and screening means beneath said supportmeans for retaining debris for removal with the supporting device fromthe casting box.

RALPH P. DAVIS.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 521,452 Adams June 19, 1894 779,455 Willits Jan. 10, 19051,119,400 Cappell Dec. 1, 1914 1,417,223 Anderson May 23, 1922 1,736,363Ramsden Nov. 19., 1929 1,776,394 Powell Sept. 23, 1930 2,488,262Bengelsdorf Nov. 15, 1949 2,568,905 Wiehsner Sept. 25, 1951

